Practice with z scores and tables

Front

What does the z-table represent?

Back

The z-table gives the percent of data at or below a z-score.

Front

What is the z-score for a value that is 3.26 standard deviations below the mean?

Back

z = -3.26.

Front

What percent of scores are below a z-score of -3.26?

Back

0.06%.

Front

In a normal distribution, what percent of the data falls within 2 standard deviations of the mean?

Back

Approximately 95%.

Front

What is the area under the curve between z = -1.56 and z = 0.67?

Back

0.6892.

Front

If a dataset is normally distributed, what does it mean for the data?

Back

It means the data follows a bell-shaped curve, where most values cluster around the mean.

Front

What is the mean and standard deviation of the shelf life of a particular dairy product?

Back

Mean = 12 days, Standard Deviation = 3 days.

Front

What percent of products last between the mean and one standard deviation above the mean in a normal distribution?

Back

34%.

Front

How do you calculate the z-score for a given value?

Back

z = (X - μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation.

Front

What is the significance of a z-score of 0?

Back

A z-score of 0 indicates that the value is exactly at the mean.